1. Field of the Invention
The present invention relates to an ink-jet printing apparatus and an ink-jet printing method.
2. Description of the Related Art
An ink-jet printing apparatus has been known conventionally in which a print head having a plurality of printing elements which generate power for discharging ink is driven so that ink can be discharged onto a printing medium for printing an image. It has been known that various temperature controls are executed based on temperatures detected by a temperature sensor provided in the print head in the ink-jet printing apparatus. Generally, a diode sensor having excellent heat responsiveness is used as the temperature sensor in the print head.
Such a diode sensor varies in characteristics due to manufacturing errors, and there is a possibility that a temperature deviation from an actual temperature may be detected due to error from a reference characteristic. In order to address this problem, Japanese Patent Laid-Open No. 7-209031 discloses an ink-jet printing apparatus internally having a temperature sensor separately from a diode sensor so that a detected value from the diode sensor can be corrected based on the detected value from the temperature sensor to calculate a correct temperature. Use of a thermistor of as the temperature sensor has also been known because manufacturing errors for thermistors do not occur easily though thermistors have lower heat responsiveness than that of diode sensors. More specifically, it is disclosed that, in a case where, for example, a detected temperature from a thermistor before printing is Tthr [° C.] and a detected temperature from a diode sensor is Tdef [° C.], a correction value Tadj (=Tthr−Tdef) is added to the detected temperature Tdi from the diode sensor under the temperature control to calculate a correct temperature.
Japanese Patent Laid-Open No. 7-209031 further discloses that a detected value from the diode sensor is corrected based on a detected value from the thermistor every predetermined period of time. It is disclosed that even when the correction is not performed on the diode sensor at a proper time point, the correction may be performed at the next time point so that the accuracy of the correction of the detected value from the diode sensor can be increased with a lapse of time.